This invention relates generally to hardware for mounting an upright window sash to swing between closed and open positions in a window frame.
Swingable window sashes generally fall into two categories. One is an awning-type sash which is supported to swing between closed and open positions about a generally horizontal pivot axis which is usually located adjacent the upper sides of the sash and the frame. When the sash is swung outwardly about the pivot axis, the lower portion of the window is opened to vent fresh air into the room while the downwardly inclined sash serves as an awning to shed rain and to keep the rain from having a clear path to enter the room through the window.
Another type of swingable window sash is a casement sash which is supported to swing between closed and open positions about an upright axis located near one upright side of the sash. Conventionally, the pivot axis is also located near the adjacent upright side of the window frame so that, when the sash is swung from its closed position through 90 degrees or more, it extends outwardly from the side of the frame and leaves virtually the entire area of the window opening completely unobstructed. A completely unobstructed window opening is desirable not only from the standpoint of improving the view through the opening but also to permit persons to have clear egress through the opening in the event of an emergency condition in the room.
Some casement window sashes have the capability of being located in a position to enable both sides of the window pane to be easily washed from inside the room. This is effected by causing the pivot axis of the sash to shift laterally toward the center of the frame as the sash is opened so that both sides of the pane of the open sash are accessible through the window opening.
One type of casement window sash has the capability of being selectively located either in a normal egress position or in a wash position. In order to convert such a sash between positions, it is necessary to open the sash, to manually adjust the window supporting hardware at both the top and bottom of the window and then to manually move the window between the egress and wash positions.